From: Todd Kjos <tkjos@android.com>
Date: Thu, 29 Jun 2017 12:01:36 -0700
Subject: [PATCH] binder: use group leader instead of open thread
References: bnc#1060662
Patch-mainline: v4.12.10
Git-commit: c4ea41ba195d01c9af66fb28711a16cc97caa9c5

commit c4ea41ba195d01c9af66fb28711a16cc97caa9c5 upstream.

The binder allocator assumes that the thread that
called binder_open will never die for the lifetime of
that proc. That thread is normally the group_leader,
however it may not be. Use the group_leader instead
of current.

Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/android/binder.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 157bd3e49ff4..9393924ae8e8 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3460,8 +3460,8 @@ static int binder_open(struct inode *nodp, struct file *filp)
 	proc = kzalloc(sizeof(*proc), GFP_KERNEL);
 	if (proc == NULL)
 		return -ENOMEM;
-	get_task_struct(current);
-	proc->tsk = current;
+	get_task_struct(current->group_leader);
+	proc->tsk = current->group_leader;
 	INIT_LIST_HEAD(&proc->todo);
 	init_waitqueue_head(&proc->wait);
 	proc->default_priority = task_nice(current);
-- 
2.14.2